The photos were widely circulated after the event. LE must have just taken these photos from one of the many emails circulating and put together an AAR to help it out the LE community. I took a a Mexico-based Executive Protection course in San Diego last month and they had a similar write-up on this incident. At the course they had maybe 50 pictures of this incident and many other recent violent events in Northern Mexico. Contact them and maybe they will send them out.